Captive-born Kroombit tinker frog boosting wild populations in Queensland
In 2024, the Currumbin Wildlife Sanctuary, Queensland Frog Society and Queensland Parks and Wildlife Service team recorded the calls of the first captive-born Kroombit tinker frogs released into the wild a year earlier.
Senior Conservation Officer Harry Hines said it was a significant moment for amphibian conservation in Queensland.
“Tinker frogs face extinction, and we think 3 of the 6 species are probably already extinct,” Mr Hines said.
“Kroombit tinker frogs are small and rarely seen in the wild, so the only way we can measure the survival of released frogs is to listen for their distinctive calls.
“This species is only found in the Kroombit Tops National Park, south-west of Gladstone, where we estimate less than 150 remain in the wild.
“The Currumbin Wildlife Sanctuary breed-for-release program gives this critically endangered species a chance of survival.”
In 2017, the Queensland Government launched a program with Currumbin Wildlife Sanctuary to breed genetically diverse Kroombit tinker frogs, which could be re-introduced to the existing natural population or re-populate sites where frogs have gone locally extinct.
The team collected the first Kroombit tinker frogs from the wild in 2018 and started breeding pairs. Over the next 3 years, they successfully bred the species, observing, for the first time, its eggs, tadpoles and froglets.
Currumbin Wildlife Sanctuary amphibian specialist Michael Vella explained the tinker frog recovery program was the only one in Queensland.
“By 2024, our team had successfully reared close to 300 Kroombit tinker frogs that are getting readied for release,” Mr Vella said.
“Kroombit tinker frog populations are affected by habitat degradation, but the amphibian chytrid fungus, which causes disease in the frogs, is likely the most significant factor in their decline.
“We have built the frog lab—a state-of-the-art facility—at Currumbin Wildlife Sanctuary, where we manage the breeding and care of the captive frogs. In this lab, we observe behavioural and reproductive information never recorded before.
“Frog ecologists also support the captive breeding program, generously sharing their knowledge to increase the tinker frog’s survival chances.”
At the Kroombit Tops National Park, the team conducts regular surveys of the species and assessment of its habitat and the impacts of pest species. Fieldwork can include frog searches, gathering bio-recordings, and pest control measures, like fencing to keep feral pigs out.
When the time is right and the weather permits, the team looks forward to releasing more frogs into the wild. The most significant measure of the program’s success will be hearing Kroombit tinker frog calls for years to come.